Pulmonary macrophages exhibit a dose-dependent pattern in phagocytizing particles. Following engulfment, these macrophages are subsequently excreted with sputum, rendering macrophages and particles visible and quantifiable under light microscopy. Notably, elemental carbon within the mammalian body originates exclusively from...

The study received approval from the Medical Ethics Committee of the Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention (NIOHP201604), with written informed consent obtained from all subjects prior to the study and biological sample collection. For this study, carbon black ...